It happens everywhere geographically. I can be on a call via HF and it's bad, switch to the handset and the call is crystal clear. I have zero call quality issues with the 710 itself.

I have tried separating my key fob and the phone by as much as is possible within the TCH cabin. Where the phone is doesn't seem to have much effect either. The status of the HVAC seems to be irrelevant as well.

I need to take the time to borrow the wife's non Moto BT phone and pair it to my car, and also try my phone in her Prius.

On a related note, how does one change the BT mic volume on a NON-NAV TCH?